diff --git a/include/boost/function/detail/prologue.hpp b/include/boost/function/detail/prologue.hpp
index 5960134..524f710 100644
--- a/include/boost/function/detail/prologue.hpp
+++ b/include/boost/function/detail/prologue.hpp
@@ -21,7 +21,7 @@
 #  include <boost/config.hpp>
 #  include <boost/function/function_base.hpp>
 #  include <boost/mem_fn.hpp>
-#  include <boost/type_traits/is_same.hpp>
+#  include <boost/type_traits/is_integral.hpp>
 #  include <boost/preprocessor/enum.hpp>
 #  include <boost/preprocessor/enum_params.hpp>
 #  include <boost/preprocessor/cat.hpp>
diff --git a/include/boost/function/function_template.hpp b/include/boost/function/function_template.hpp
index dce0b00..dd8f199 100644
--- a/include/boost/function/function_template.hpp
+++ b/include/boost/function/function_template.hpp
@@ -285,7 +285,7 @@ namespace boost {
 #ifndef BOOST_FUNCTION_NO_ENABLE_IF
                             ,typename detail::function::enable_if<
                             (::boost::type_traits::ice_not<
-                             (is_same<Functor, int>::value)>::value),
+                             (is_integral<Functor>::value)>::value),
                                         int>::type = 0
 #endif // BOOST_FUNCTION_NO_ENABLE_IF
                             ) :
@@ -338,7 +338,7 @@ namespace boost {
 #ifndef BOOST_FUNCTION_NO_ENABLE_IF
     typename detail::function::enable_if<
                (::boost::type_traits::ice_not<
-                 (is_same<Functor, int>::value)>::value),
+                 (is_integral<Functor>::value)>::value),
                BOOST_FUNCTION_FUNCTION&>::type
 #else
     BOOST_FUNCTION_FUNCTION&
@@ -594,7 +594,7 @@ public:
 #ifndef BOOST_FUNCTION_NO_ENABLE_IF
            ,typename detail::function::enable_if<
                             (::boost::type_traits::ice_not<
-                          (is_same<Functor, int>::value)>::value),
+                          (is_integral<Functor>::value)>::value),
                        int>::type = 0
 #endif
            ) :
@@ -620,7 +620,7 @@ public:
 #ifndef BOOST_FUNCTION_NO_ENABLE_IF
   typename detail::function::enable_if<
                             (::boost::type_traits::ice_not<
-                         (is_same<Functor, int>::value)>::value),
+                         (is_integral<Functor>::value)>::value),
                       self_type&>::type
 #else
   self_type&